The present invention relates to a canister module for treating fuel vapor generated from a fuel tank with adsorbent such as activated carbon or the like.
As an apparatus for treating vapor generated from a fuel tank of a vehicle, there has conventionally been known a canister apparatus in which a recess portion (i.e., a gap) is provided between a pair of adsorbent chambers so as to extend to substantially the entire height of the adsorbent chambers so that heat of adsorption generated in each of the adsorbent chambers can be released also into the recess portion, thereby inhibiting temperature rise of adsorbent to prevent its adsorbing property from being degraded (see for example Japanese Utility Model Publication No. H6-27818).
One adsorbent chamber of the canister apparatus is provided with a tank-communicating opening, which communicates with the fuel tank, and with a purge port-communicating opening, which communicates with a fuel consumption system. The other adsorbent chamber is provided with an atmosphere-communicating opening. In addition, many kinds of peripheral parts are connected to the above-mentioned openings so as to control circulation and pressure of vapor. For example, a pressure control valve or the like for controlling the internal pressure of the fuel tank is connected to the tank-communicating opening. A filter apparatus or the like for removing dust in the air, which is to be introduced into the adsorbent chambers, is connected to the atmosphere-communicating opening. These components, which are composed as separate parts from the canister apparatus, are mounted fixedly in the vicinity of a housing of the canister apparatus by means of supporting members such as stays or the like. There is a case where some of peripheral parts are received in a separate vessel from the housing of the canister apparatus to provide a unit and such a unit is secured in the vicinity of the canister apparatus.
However, in the conventional setting structure of the peripheral parts, the parts are required to be independently secured on the wall or the like of an engine room, leading not only to increase in the number of the parts, but also to time consuming operations, thus increasing a cost. Even when the peripheral parts are composed as a unit with utilization of a plastic housing, the number of the parts inevitably increases due to addition of the plastic housing.
When the recess portion is provided between the adsorbent chambers of the canister apparatus, the width of the canister apparatus increases, leading to increase in space required for installation of the canister apparatus. In such a circumstance, arrangement of the many kinds of peripheral parts around the canister apparatus occupies a considerable space of the engine room due to such devices and parts, exerting possibly an influence on arrangement of the other parts.
An object of the present invention is to provide a canister module in which a canister housing, peripheral parts and the like relevant to a canister are put together into a compact body, thus making it possible to decrease not only a space required to mount these parts on a vehicle, but also the number of the parts.
In order to attain the aforementioned object, a canister module of the present invention comprises: a canister housing in which a plurality of adsorbent chambers filled with adsorbent are provided side by side so that a gap is formed between opposite side walls for defining the adsorbent chambers, different parts from interior parts received in said canister housing are received in said gap.
According to such a structure, it is possible to effectively release heat of adsorption generated in the adsorbent chambers outside the chambers in the same manner as the conventional apparatus, because of the gap provided between the opposite side walls, which define the adsorbent chambers. Moreover, the different parts from the interior parts, which are received in the canister housing, are received in the gap provided between the adsorbent chambers so that the gap can be utilized effectively as a receiving space for the parts, in addition to radiation purpose of heat. Accordingly, the canister housing and the different parts can be put together into a single module, thus making it possible to decrease a space required to mount them. Such a compact unit structure causes the support member or the like to be commonly used to mount the different parts or to be omitted, leading to the decreased number of the parts and permitting reduction in cost.
In the canister module of the present invention, canister-peripheral parts serving as the different parts, which are connected to the adsorbent chambers through communicating openings provided on the canister housing, may be received in the above-mentioned gap. According to such a structure, it is possible to mount detachably the canister housing and the peripheral parts, which are to be connected to the communicating openings of the canister housing, on a vehicle in an assembled state. It is therefore possible to carry out easily a mounting operation or a removing operation on the vehicle in comparison with a case where connecting operations for communicating openings and peripheral parts are carried out after they are mounted on a vehicle.
The canister module of the present invention may further comprise a support member, which is detachable relative to the canister housing, and the canister-peripheral parts may be secured on the support member. In addition, the other canister-peripheral parts may be secured on the support member. Any parts other than the canister-peripheral parts may be secured on the support member. According to such a structure, it is possible to secure a plurality of canister-peripheral parts and the like on the single support member to provide a sub-assembly. Such a sub-assembly can be mounted on the canister housing so that many kinds of parts can easily be incorporated into the gap of the housing.
At least part of the support member may be put into the above-mentioned gap, and the canister-peripheral parts may be secured on the part, which is put into the gap. According to such a structure, it is possible to receive easily the canister-peripheral parts in the gap of the canister housing.
The part of the support member, which is put into the gap, may have vertical wall portions extending along the side walls of the adsorbent chambers and a cross portion for connecting the vertical wall portions. According to such a structure, it is possible to prevent the support member from improperly moving within the gap, permitting to hold securely the canister-peripheral parts.
In the present invention, it is possible to cause the canister-peripheral parts received in the gap or the support member to function as a device for releasing heat of adsorption in the adsorbent chambers into the above-mentioned gap, by for example forming the canister-peripheral parts and the support member of material having a high thermal conductivity or adopting a shape by which a high heat radiation effect can be provided.
The term xe2x80x9ccanister modulexe2x80x9d used in the present invention means an object in which a canister apparatus composed of the canister housing and internal parts received therein and the above-mentioned different parts are put together into a single module.